BAGHDAD, Iraq (CNN) --Two weeks after coalition airstrikes plunged Baghdad into darkness, power has returned to the Iraqi capital -- but only for short periods of time and in scattered areas, a senior U.S. military official told CNN.

The lack of electricity and water has heightened tensions in Baghdad. To keep food from spoiling, residents have had to resort to buying blocks of ice from resourceful entrepreneurs with generators and ice machines, but most have not had access to the ice.

The U.S. Central Command's deputy director of operations, Brig. Gen. Vincent Brooks has said restoring electricity and fresh water supplies and aiding hospitals are priorities.

Many Baghdad hospitals have been able to fire up their electric generators in recent days thanks to fuel trucks getting through, guarded by Marines to prevent looting.

"Over the last four to five days we've been meeting with the top electrical engineers of Baghdad and the surrounding area to try to get the electrical grid back up," Marine Maj. Don Broton told CNN.

He said it took three or four days to reassemble the main staff of Iraq's electrical authority. The United States made a call for Iraqis with technical expertise to return to work.

The effort has managed to restart two sub-stations in southern Baghdad, as well as six diesel plants, all coming online Wednesday.

There were plans to restart several more sub-stations today, but those were reassessed, according to Broton. Restarting the plants requires a huge burst of power -- literally jump-starting the entire plant.

The power to do that does not exist in Baghdad right now, Broton said, though there is sufficient power in the northern city of Kirkuk.

The military Friday plans to fly Iraqi engineers by helicopter along the transmission lines that run from Kirkuk. They will inspect the lines with the idea using the Kirkuk power to jump-start the Baghdad plants.

Abdel Hamid Mehdi, a senior official with the National Supply Center -- which runs the electrical system -- said downed power lines are one of the biggest barriers to getting the power back on in Baghdad.

"There are many, many cuts in the lines," he said. "Most of the lines are damaged." According to Mehdi, that includes the lines that link together the various sub-stations.